High-speed multiple-action press



March 18, 1969 v. J. BALUNAS, JR. ET AL 3,433,048

HIGH-SPEED MULTIPLE-ACTION PRESS Sheet Filed Dec. 2, 1966 INVENTORS. j VlNCENT J. BALUNA Tj IOMAS R. HITCH ATTORNEYS March 18, 1969 V.J. BALUNAS, JR, ET AL 3,433,048

HIGH-SPEED MULTIPLE-ACTION PRESS Sheet Filed Dec. 2, 1966 INVENTORS. VINCENT J. BALUNAS, JR. 8 THOMAS R. HITCH BY Meym,7d%my A? rid? ATTOR NEYS United States Patent 3,433,048 HIGH-SPEED MULTIPLE-ACTION PRESS Vincent J. Balunas, In, Wallingford, and Thomas R. Hitch, Aldan, Pa., assignors to E. W. Bliss Company, Canton, Ohio, a corporation of Delaware Filed Dec. 2, 1966, Ser. No. 598,779 U.S. Cl. 72-417 Int. Cl. B21d 43/02; B21j 9/18 4 Claims ABSTRACT OF THE DISCLOSURE This invention relates to the art of high-speed forming presses, and more particularly an improved multiple-action press.

The present invention is particularly applicable to use in a double-action press, and it will be described with particular reference thereto; however, it will be appreciated that the invention has broader applications and may be used in various multiple-action metal working machines or presses.

Double-action presses of the prior art comprised a frame, an outer slide, adapted to be reciprocated with respect to the bed of the press, in order to clamp the work upon the bed in a position to permit dies carried by an inner slide, to do their work. The arrangement is such that the outer, work holder slide, dwells during the period the inner slide performs its operation.

In conventional prior art machines, the outer slide dwells for 110 of the 360 cycle of the machine. For many operations, this is an unnecessarily long period of time. Naturally, the longer the dwell period the less time there is in the cycle to strip the work from the bed, remove the work from the machine, and replace it with a new piece of work to be deformed. Consequently, a machine having a 110 dwell is limited in terms of the amount of work it can produce, because during a significant portion of the operating cycle, the workpiece is held on the bed while no productive work is performed on it.

The present invention is addressed to a double-action press of improved design which obviates certain disadvantages of the prior art machines. More particularly, the novel press of the present invention has an improved timing cycle which condenses the productive portion of the machines operating cycle, i.e., that portion of the cycle during which the workpiece is held in place before and deformed by one or more dies. The present invention is capable of reducing the standard 110 dwell to a 64 dwell. This means that the deformed workpiece can be stripped from the bed of the machine earlier in the cycle, and thus made available for transfer and handling during a longer period of the cycle. In addition, more time is allotted in the condensed cycle to feed a new workpiece to the bed. Consequently, it is possible through the use of the novel timing cycle of the present invention, to increase the rate of productivity of the machine by decreasing the time of a cycle.

In accordance with the present invention, there is provided, in a double-action power press, including in combination a frame, an outer slide and an inner slide mounted for reciprocation in said frame, and means operative to reciprocate the inner slide with simple harmonic mo- 3,433,048 Patented Mar. 18, 1969 tion: improved means operative to reciprocate the outer slide with modified harmonic motion providing a bottom dwell period of less than comprising, a driven gear formed with an eccentric, a pitman connected to the eccentric, a pivot link having a free end operative for pivotal movement about a fixed end, a rocker assembly having first and second rocker arms, a link having one end connected to the first rocker arm and its other end interconnecting the pitman and the free end of the pivot link, and a connecting rod having one end connected to the outer slide, and its other end connected to the second rocker arm, whereby the non-productive portion of the press operating cycle is condensed.

It is, therefore, an object of the invention to provide an improved double-action power press capable of higher operating speeds than the prior art machines.

A further object of the invention is to provide an improved double-action power press having a shorter dwell period than the prior art machines.

Yet another object of the invention is to provide an improved double-action power press which allows more time to strip, remove and replace workpieces during the machines cycle.

These and other objects and advantages will become apparent from the following detailed description of a preferred embodiment of the invention when read in connection with the accompanying drawings, in which:

FIGURE 1 is a schematic view of a vertical section showing a preferred embodiment of the invention;

FIGURE 2 is a schematic view of a pictorial representation showing a preferred embodiment of the invention; and

FIGURE 3 is a motion diagram showing the motion of the inner slide, and a comparison of the outer slide motion, in accordance with the present invention, with the motion of the outer slide of a conventional press.

Referring now to the drawings, wherein the showings are for purposes of illustrating a preferred embodiment of the invention only, and not for the purpose of limiting the same, FIGURES 1 and 2 show a press frame 2, an outer or work holding slide 4, and an inner or die holding slide 6.

Mounted within the press frame 2 is a large gear 8 mounted for rotation on shaft 10. The gear is driven by pinion 12 mounted on shaft 14 which is attached to a prime mover of a conventional design, not shown. Gear 8 is formed with a first eccentric 16 and a second eccentric 18, to which are connected, respectively, a first pitman 20 and a second pitman 22.

The transmission supplying modified harmonic motion to outer slide 4 will now be described. Associated with bifurcated free end 24 of pitman 22 is pivot link 26. This link has a bifurcated free end 28 adapted to pivot around fixed end 30 held in place by pivot 32. The transmission further includes a rocker assembly designated generally as 34, comprising rocker shaft 36, a first rocker arm 38 having a bifurcated end, and second rocker arm 40 having a bifurcated end. Interconnecting rocker arm 38 with pivot link 26 and pitman 22 is link 42 having a first end operatively received within the bifurcation of end 24 of pitman 22 which in turn is operatively received within the bifurcation of end 28 of pivot link 26. These three elements are held in cooperative relationship by pin 46. The opposite end of link 42 is adapted to be received with the bifurcation of rocker arm 38, and is held in placed by pin 44.

The bifurcated end of rocker arm 40 is connected, as by pin 48 to connecting rod 50. Pin 52 mounted in the lower end of connecting rod 50 is adapted to be received in retaining block 54, which together with upper tubular, flanged housing 56, and lower tubular, flanged housing 58, collar 60, and height adjusting wheel 62, form a suitable means for adjustably connecting the lower end of connecting rod 50 with outer slide 4.

The transmission for supplying simple harmonic motion to inner slide 6 comprises pitman and pin 64 which is connected to inner slide 6 through the same adjustable connecting means used to join the lower end of connecting rod 50 to outer slide 4.

In order to operate the inner and outer slides at opposite ends of the machine, the various parts described above can be duplicated. The general arrangement of duplicated parts is partially shown by gear 8a, pinion 12a and shaft 14a, (see FIGURE 1).

The motion diagram shown in FIGURE 3 depicts an inner slide curve and a comparison between the outer slide curve in accordance with the device of the present invention, and the outer slide curve of a conventional machine. The shaded portion between the two outer slide curves defines the extent to which the present invention condenses the productive portion of the machines cycle. The shaded portion at the left side of the diagram represents additional time during which a new workpiece can be fed to the bed of the machine before the dwell period begins, and the shaded portion to the right of the diagram represents the additional time the present invention allows for the stripping and removal of a deformed workpiece. Since the present invention allows earlier access to the workpiece and more time for transferring and handling new and deformed workpieces, the over-all operating cycle of the machine can be speeded up to make the machine more productive.

The present invention has been described in conjunction with certain structural embodiments; however, it is to be appreciated that various structural changes may be made in the illustrated embodiment without departing from the intended scope and spirit of the present invention as defined in the appended claims.

Having thus described our invention, we claim:

1. A reciprocating mechanism for a slide in a power press comprising:

(a) a rotatable driven gear having opposite side faces,

(b) a driving eccentric on one of said side faces,

(c) a pitman having one end connected with said eccentric and its other end defining a free pitman end,

(d) a pivot link having one end pivotally connected on a fixed pivot axis substantially parallel to the rotational axis of said gear and its other end defining a free pivot link end,

(e) a rocker assembly including,

(aa) a first rocker arm and (bb) a second rocker arm,

(f) a connecting link having one end connected to said first rocker arm and its other end defining a free connecting link end,

(g) said free pitman end, said free pivot link end and said free connecting link end being connected on a common connecting axis substantially parallel to the rotational axis of said gear, and

(h) a connecting rod having one end connected to said second rocker arm and its other end connectable with said slide.

2. The mechanism of claim 1 wherein said fixed pivot axis for said one end of said pivot link is located between said first rocker arm and said eccentric, and below a plane passing through both the rotational axis of said gear and said common connecting axis.

3. The mechanism of claim 1 and further including another eccentric on the other side face of said gear, said other eccentric being angularly displaced from said first eccentric, and another pitman having one end connected with said other eccenrtic and another end connectable with another slide.

4. The mechanism of claim 1 wherein said pivot link directs movement transferred to said common connecting axis through said eccentric and pitman to a controlled arcuate path, and the dwell period of said connecting rod is less than degrees.

References Cited UNITED STATES PATENTS 1,564,986 12/1925 Thompson 724l7 1,986,410 1/1'935 Rode 724l7 2,579,078 12/1951 Johansen 724l7 3,130,699 4/1964 Ward 72450 CHARLES W. LANHAM, Primary Examiner.

L. A. LARSON, Assistant Examiner.

US. Cl. X.R. 

